
\chapter{Introduction}

This document documents the design of \TC, a new Chess variant which incorporates time travel as a core game mechanic, and the construction of a computer implementation of \TC to make the game playable by pairs of humans. 

\section{Aims}
\label{chapter-aims}

\TC has two main (interrelated) aims.
\label{aims}

The first aim of \TC is to have an extremely high \textit{cognitive load}. In layman's terms, this can be thought of as ``how difficult the game is to play''. However this definition is insufficient, because `difficulty' is a broad term which can refer to many different challenges, including non-mental ones. Specifically, `cognitive load' in this context refers to the level of mental activity involved in playing the game properly.  It is a function of the amount of processing that must be done, and the amount of game state information that must be stored in working memory in order to play. \cite{paas2003cognitive}

Determinants of cognitive load include the number of possible moves available to the player and the number of factors that must be considered in evaluating a possible move. The cognitive load of a game is therefore closely related to its complexity.  

Chess is generally considered to be a complex game \cite{shannon1950}, but \TC is far more complex.

This complexity helps to contribute to the second aim of \TC, which is to provide a chess variant that presents new and interesting challenges to both human and machine players, encouraging AI research to yield results useful in general Chess AI and beyond.

It's worth noting that we do not aim to implement a Time Chess AI here, but to provide the groundwork for others to build on.
